Conventional syringes have been in medical use for over a hundred years to inject medicaments into the body. These devices have protocols described in the literature for their general use and their specific use with a vast plethora of injectable drugs. Primarily supplied in two formats; empty syringes for filling from a vial of the drug, or as a pre-filled syringe. The conventional syringe is the most widely known and understood of the injection devices. Who hasn't seen a conventional syringe injection performed in the movies at least? The point being that syringe injections are familiar and therefore, lack a “fear-of-the-unknown” aspect even though the patient may be afraid of injections themselves. In contrast, the so-called “autoinjectors and other newer and sometimes “automated” medicament injection devices are unknown to the general population. An increasing segment of the population however, is finding themselves in need of receiving injections or giving injections and need assistance such as cannot be provided by the plain syringe presentation. Receiving injections can be frightening and receiving injections from an unknown device which, by all appearances, will lack bedside manner and gentleness, can further compound injection anxiety beyond that which may be experienced from the familiar. In the hands of a skillful operator, a conventional syringe injection can be gentle and non-frightening, especially if the one receiving the injection doesn't have to watch. If the one giving the injection is the one receiving the injection, not looking while they perform the injection is not an option, at least when using a conventional syringe by itself. Also, syringes require a degree of dexterity and technique to administer.
Considering the non-conventional (non-syringe presentation) types of medicament injection devices, be they automated or not so, their unknown or mysterious and non-obvious nature of their operation can cause the one giving an injection to question how the mechanism works and to hesitate or feel unsure they are proceeding correctly. To actuate such a medicament delivery device, such as an autoinjector, the user may be required to execute a series of operations that they have never even seen performed. For example, to actuate some known autoinjectors, the user must remove a protective cap, remove the locking device, place the injector properly against the body, and then press a button to actuate the device, and finally, hold the device in place on the body for a certain amount of time in order to completely dispense the drug before the needle is withdrawn from the tissue. These steps are not necessarily any more difficult than giving an injection with a conventional syringe, however, the steps may be unknown or unfamiliar or in question. Besides the possible increased anxiety or hesitancy presented by the unknown, there is also a greater possibility of improper use. For example, since with these injector devices, you cannot see the emptying of the medicament from its container, there is the possibility of removal of the needle too soon from the tissue before the full required dosage of the drug has been administered.
The likelihood of improper use of known medicament delivery devices can be compounded by the nature of the user and/or the circumstances under which such devices are used. For example, many users are not trained medical professionals and may have never been trained in the operation of such devices. Moreover, in certain situations, the user may not be the patient, and may therefore have no experience with the medicament delivery device.
Some known medicament delivery devices include printed instructions to inform the user of the steps required to properly deliver the medicament. Such printed instructions, however, can be inadequate in a society which “reads the instructions as a last resort.” Moreover, because some known medicament delivery devices, such as for example, autoinjectors and pen injectors or the like can be compact, such printed instructions may be too small to read and comprehend. If the instructions are printed on paper, the instructions can become separated from the device.
Some known medicament delivery devices can produce sounds, such as a beep or tones that can be provided as prompts to users of medicament delivery devices. The sounds of such known devices and the manner in which the sounds are produced, however, provide limited information to the user or the user may not know what the “tone” emitted means. For example, some known medicament delivery devices produce a single tone sound or LED light going off to indicate that a proper dosage has been delivered, but cannot provide a user with instructions associated with the use of the device or directions in a step-by-step presentation. One known device has attempted to remedy this lack of instructional feedback by providing synthesized voice instructions, yet such a voice system as they illustrate is only sixty seconds of synthesized voice. Furthermore, there are patients speaking many native languages. Synthesized voice may not be easily understandable, especially if the quality is lacking. The sound level and/or the quality of the sound produced by such known medicament delivery devices is limited by the size, performance, and/or cost associated with sophisticated human language synthesizing systems, especially in one-time usage devices. Furthermore, synthesized voice systems can not equal the quality of a recorded actual human language spoken by a native of that language.
Thus, a need exists for medicament delivery systems and/or devices that provide instructions, messages, information and/or directions by an actual professional orator speaking in a calm and clear voice of a multitude of languages. Furthermore, biofeedback in the form of a varying tonal frequency and/or haptic vibration frequency could provide information as to how the injector was being held against the skin, such as the perpendicularity to the surface and the steadiness of its position. This could then allow for user initiation of the injection without actually watching the device.
The injector group which operates on cartridges as the medicament container often provides the benefit of multidose usage from the cartridge by replacing the needle between injections (such as insulin pens). To this inventor's knowledge, these devices only work with needles which are only of size and length for subcutaneous use. However, many drugs are not available in cartridges but rather, are provided in vials for use with standard syringes, or are contained within pre-filled syringes primarily made of glass. Also, many drugs require intramuscular injection which necessitates longer and larger gauge needles which are not accommodated by the known devices. These devices do provide for automated dispensing of “dialed in” quantities of medicament, yet they often do little to alleviate needle phobia as experienced by a large portion of the population. That is, most of these devices do provide dosage injection automation, yet do not automate the insertion or removal of the needle into or from the patient. Some of the known devices could be used on multiple patients (since the needle is changed between injections) but such devices are generally not intended for such use since they provide multiple dosing from a single cartridge (such as insulin) and thus, they become personal medicament dosing devices.
Thus, there is a need for injection devices which can use longer and larger gauge needles than are used with subcutaneous injections. Further, there is need for a reusable device which can work with drugs contained in vials for use with standard syringes or with pre-filled syringes; a standard presentation for which the largest number of drugs are available. Further, there is need for automated insertion and removal of the needle without being observable by the user or requiring user intervention. Further, there is need for an automated injection device which can be utilized in professional settings on multiple patients.
The jet injectors can provide for use among multiple patients because their jet can be delivered through a disposable jet tip or nozzle. This nozzle is what touches the patient and it can be provided sterile and then disposed after each injection. Further, the disposable nozzle has no needle, and therefore, there is no chance of “needle stick” which has become a large concern in the professional settings where many injections are given by a practitioner thus raising their chance of the occurrence. Therefore, the disposable nozzle provides for jet injector use in professional settings such as clinics and hospitals where multiple patients can be injected from the same reusable injector. However, for drugs to be administered in these settings with a “jet-injector”, they must be approved for injection by jet (as opposed to needles) and the majority of drugs are not approved for this mode of application. Furthermore, jet injecting can introduce trauma to the tissue and are therefore, not less painful than needle injections. Jet injectors are powered by strong springs or compressed gas.
Thus, there exists a need for an injection device which can be used on multiple patients using standard needles which provide both sterility between patients and also protect against accidental needle stick when the injection is complete and the needle is being disposed. Further, there is need for the above facilities which can be administered through standard needles for which the vast majority of drugs are approved.
The “Auto-injector”, so named since it is primarily intended for patient self-injection, or since they do provide some automation such as insertion of the needle into the patient's tissue, is spring or gas pressure powered and usually intended for disposal after one injection. A very few of these devices will operate a standard syringe, yet to this inventor's knowledge, not one of them has electronics as the power source which performs the injection via a standard syringe presentation. They have generally become increasingly more mechanically complicated in design, utilizing multiple springs to inject, and then retract the needle, etc. There comes a limit to what can be accomplished by springs in a practical design. For instance, one could not maintain a real-time clock calendar with injection reminder alarms of mp3 audio ringtones by using springs. Likewise, it becomes increasingly difficult to control injection forces, velocities, and accelerations with springs. Sensing of injector position or angle against the skin are another example of the limit incurred by spring powered or operated devices. Still another consequence of spring or gas power is the sudden release of potential energy as these devices are triggered. Most all of the patent texts for these devices include the words: “cocking”, “arming”, “firing”, or “firing mechanism” in phrases describing the storage or release of energy from the compressed springs or gas. These devices lack the ability to perform an injection with finesse such as can be administered by a well practiced medical professional. When the spring's energy is released to insert the needle and inject the medication, abruptness and vibration can occur as the spring's stored energy is released. Furthermore, the ability to adapt the action of the spring's force to accommodate varying forces presented by differences in liquid medication viscosities, needle gauges, and plunger forces are non-existent or would require a mechanical adjustment by the user.
Thus, there is a need for a reusable type autoinjector which can operate on a standard syringe presentation. Furthermore, there is need for an autoinjector which is mechanically simple yet contains electronics which can provide benefits not obtainable from springs or compressed gas. Further, there is need for finesse in inserting the needle, dispensing the medicament into the tissue, and removal of the needle such as can be provided with motion control algorithms and systems which can adjust to varying loads such as can be found in robotic systems. Further, there is need for sensing if and how the injector is placed against the skin, to make sure it is perpendicular to the surface, and held steady even if it is being held by the patient into an area outside of their visual range, such as in the gluteus muscle.